微创与开放经椎间孔腰椎间融合术后中期邻近节段影像学退变的比较

Comparison of adjacent segment degeneration following single-segment minimally invasive and open transforaminal lumbar interbody fusion

目的比较微创经椎间孔椎间融合术(minimallyinvasive transforaminal lumbar interbody fusion,MIS-TLIF)和TLIF治疗单节段腰椎管狭窄症术后中期邻近节段影像学退变(adjacent segment degeneration,ASDeg)的发生情况.方法收集2009年至2013年采用TLIF手术治疗L4,5单节段腰椎管狭窄症且随访时间至少5年的患者病历资料,共115例纳入研究.根据手术方式分为MIS-TLIF组38例和TLIF组77例.影像学评价指标采用腰椎前凸角(lumbar lordosis,LL)、L4, 5融合节段角(fused segment angle,FSA)、邻近节段椎间隙高度(disc height,DH)及邻近节段活动度(range of motion,ROM),术后通过Babu等的标准评估椎弓根螺钉对L3,4关节突关节的侵扰(facet joint violation,FJV).临床疗效评估采用疼痛视觉模拟评分(visual analogue scale,VAS)、日本骨科协会(Japanese Orthopaedic Association Scores,JOA)评分和Oswestry功能障碍指数(Oswestry disability index,ODI).结果 115例患者随访时间为60~73个月,平均(64.1±3.5)个月.两组患者术后5年时VAS评分、JOA评分和ODI较术前均有明显改善.术后5年随访共56例(48.7%)发生ASDeg,MIS-TLIF组患者ASDeg的发生率为31.6%,较TLIF组(57.1%)明显降低(χ^2=6.656,P<0.01).32例ASDeg仅发生于上位节段(MIS-TLIF组6例,TLIF组26例),19例仅发生于下位节段(MIS-TLIF组6例,TLIF组13例),5例同时发生于上、下位节段(均为TLIF组).术后两组邻近节段DH较术前均有降低,但MIS-TLIF组DH降低值小于TLIF组,L3,4节段MIS-TLIF组DH丢失率为4.9%±6.4%,TLIF组为8.7%±7.2%,差异有统计学意义(t=-2.761,P<0.01);L5S1节段MIS-TLIF组DH丢失率为4.7%±9.8%,TLIF组为10.5%± 11.7%,差异有统计学意义(t=-2.623,P<0.01).两组患者邻近节段ROM较术前均有增加,但MIS-TLIF组ROM增加值小于TLIF组,L3,4节段(1.1°±1.8°vs 2.3°±2.5°,t=-3.122,P<0.01),L5S1节段(0.9°±1.9°vs 1.8°±1.9°,t=-2.353,P<0.05).MIS-TLIF组中发生ASDeg者FJV的发生率为54.2%,TLIF组中发生ASDeg者FJV的发生率为47.7%,卡方检验结果显示FJV与ASDeg有关(χ^2=3.869,P<0.05).结论 MIS-TLIF及TLIF手术治疗L4,5单节段腰椎管狭窄症均可取得良好的临床疗效, MIS-TLIF术后中期ASDeg的发生率低于TLIF,且FJV与ASDeg有关.

Objective To compare the incidence of adjacent segment degeneration (ASDeg) and clinical outcomes of minimally invasive versus traditional transforaminal lumbar interbody fusion (TLIF) in the treatment of L 4,5 single-segment lumbar spinal stenosis (LSS) and explore the risk factors of ASDeg. Methods All of 115 patients with LSS who were treated by the same group of doctors from 2009 to 2013, with a minimum follow-up of 5 years. Thirty-eight patients underwent minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and 77 patients underwent traditional TLIF. Standing radiographs at the preoperative period and the final follow-up were assessed. Radiological parameters included lumbar lordosis (LL), fused segment angle (FSA), disc height (DH) and range of motion (ROM). Babu classification was used to identify facet joint violation (FJV) in patients at 5-year follow-up. Clinical outcomes were assessed according to visual analog scale (VAS) score, Japanese Orthopaedic Association (JOA) score and Oswestry Disability Index (ODI). Student's t-test, Chi-square test, and non-parametric test were used as the main statistical methods. Results The mean age of MIS-TLIF group was 58.2±8.8 years, and that of TLIF group was 54.7±11.2 years, and there was no significant difference between the two groups. The mean follow-up time was 64.5±3.8 months in the MIS-TLIF group and 63.9±3.3 months in the TLIF group, and there was no significant difference between the two groups. There were 17 cases of degenerative spondylolisthesis in MIS-TLIF group (44.7%) and 35 cases of degenerative spondylolisthesis in TLIF group (45.5%), and there was no significant difference between the two groups. There was no significant difference in DH and ROM of L 3,4, L 4,5, L5S1 between the two groups before operation. There was no significant difference in VAS, JOA and ODI scores between the two groups before operation. The VAS, JOA and ODI scores were significantly improved at the last follow-up compared with those before operation. After 5-year follow-up, 56 cases (48.7%) had ASDeg. The incidence of ASDeg was 31.6% in MIS-TLIF group and 57.1% in TLIF group, and there was statistical differences between the two groups (χ^2=6.656,P<0.01). Among them, 32 cases only had upper segment ASDeg (6 cases in MIS-TLIF group, 26 cases in TLIF group), 19 cases only had lower segment ASDeg (6 cases in MIS-TLIF group, 13 cases in TLIF group), and 5 cases had both upper and lower ASDeg (5 cases in the TLIF group). The DH of adjacent segments decreased after operation, but the loss of DH in MIS-TLIF group was smaller than that in TLIF group, including L 3,4 segments (-4.9%±6.4% vs-8.7%±7.2%, t=-2.761, P<0.01), L5S1 segment (-4.7%±9.8% vs-10.5%± 11.7%, t=-2.623, P<0.01). The ROM of adjacent segments increased in both groups, but the increase of ROM in MIS-TLIF group was smaller than that in TLIF group, including L 3,4 segments (1.1°± 1.8°vs 2.3°± 2.5°, t=-3.122, P<0.01), L5S1 segment (0.9°± 1.9°vs 1.8°±1.9°, t=-2.353, P<0.01). The incidence of FJV was 54.2% in patients with ASDeg in MIS-TLIF group and 47.7% in patients with ASDeg in TLIF group. Chi-square analysis showed that FJV was related to ASDeg in both groups (χ^2=3.869,P <0.05). Conclusion Both of the two surgical methods have good clinical effects on L 4,5 single-segment LSS. The incidence of AS-Deg after MIS-TLIF is lower than that of TLIF. FJV is a risk factor for ASDeg.